Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora

A Textbook of Botany for Colleges and Universities; Volume 2

Preliminary Revision of the North American Species of Echinocactus, Cereus, and Opuntia; Volume 3

Morphology of Angiosperms

Fundamentals of Plant-Breeding

Morphology of Gymnosperms

Morphology of Angiosperms : (Morphology of Spermatophytes. Part Ii)

Textbook of Botany for Colleges and Universities, Part 1

Botany of Western Texas

Evolution of Sex in Plants

The Evolution of Sex in Plants